1. Field of the Invention
This invention relates to a supersonic ophthalmic measuring apparatus for measuring the distance between various regions of an eye to be examined such as the eye axis distance with a supersonic probe brought into contact with the cornea of the eye to be examined.
2. Related Background Art
There is known an apparatus of the soft type in which water is poured into a rubber bag provided at the end of a supersonic probe and the supersonic probe is brought into contact with the cornea of an eye to be examined to thereby measure the eye axis length. There is also known an apparatus using a supersonic probe of the hard type which eliminates the cumbersome operation described above. Apparatuses of this type which can measure not only the eye axis distance but also the shape
proposed in U.S. Pat. No. 4,764,006 and Japanese Patent Application No. 62-51785 (corresponding to U.S. Ser. No. 162,250).
Now, where measurement is effected by the use of the conventional supersonic probe, particularly, the supersonic probe of the hard type, the cornea is deformed and as a result, the measurement of the eye axis length is inaccurate.